Guidance

NHS Diabetic eye screening pathway standards from 1st October 2024

Updated 10 December 2024

Applies to England

1. Introduction

This document presents the revised national screening standards for the NHS Diabetic Eye Screening Programme (DES) and applies to data collected from 1st October 2024.

The UK National Screening Committee (UK NSC) recommends diabetic eye screening for persons on the programme register who:  

• are aged 12 years and over
• have a diagnosis of diabetes mellitus (excluding gestational diabetes)
• have perception of light in at least one eye

The NHS DES programme has responsibility for implementing this policy. Theprogramme service specification for NHS providers is available as part of the public health functions exercised by NHS England. 

The aim of the diabetic eye screening programme is to make sure there is equal access to uniformed and quality assured screening across England and that people with diabetes are provided with high quality information so they can make an informed choice about whether to attend screening.

Screening guidance documents on GOV.UK link to a central glossary of terms and further information on NHS population screening.

2. Pathway Standards

2.1 DES-PS01: Routine digital screening (RDS) coverage

Description

This standard is split into three separate metrics; 1.1 is 12 month RDS coverage, 1.2 is 24 month RDS coverage and 1.3 is RDS offered.

1.1       The proportion of people with a due date for new or 12 month RDS who attended within the 12 month reporting period plus 6 weeks.

1.2       The proportion of people with a due date for 24 month RDS who attended within the 24 month reporting period plus 6 weeks.

1.3      The proportion of people with a due date for 12 and 24 month RDS who were offered an RDS appointment which was due to take place within the 12 month reporting period plus 6 weeks.

Rationale

This standard gives an indication of the acceptance of the screening test in people who are eligible for screening.

To maximise the impact of the screening programme all eligible people should be offered an appointment for RDS unless they are suspended or excluded.

Due dates are inferred from the last attendance dates, outcome and allocated recall timeframe.

For the denominator to be reported consistently, people with diabetes who are newly added to the register will be given a due date of 42 days after their first registration.

Definition

1.1      Numerator: number of individuals attending RDS for 12 month recall between the start of the 12 month report period and 6 weeks after the report end date and were successfully screened.

The encounter can be for ‘RDS’ or ‘RDS in Hospital eye services (HES)’

1. Denominator: number of individuals who had a due date for new or 12 month screening during the 12 month report period.

1.2      Numerator: number of individuals attending RDS for 24 month recall between the start of the 24 month report period and 6 weeks after the report end date and were successfully screened.

The encounter can be for ‘RDS’ or ‘RDS in HES’.

1. Denominator: number of individuals who had a due date for 24 month screening during the 24 month report period.

2. Numerator: those in the denominator who were offered an appointment for new, 12 or 24 month RDS, which was due to take place during the 12 month report period plus 6 weeks.

This is counted differently dependent on the invitation model:

• Fixed - invitations that were issued at any time for a proposed appointment date within the reporting period.
• Partial booking systems which offer a range of dates during which the patient can arrange an appointment should use the first date in this range as the proposed appointment date.
• Open appointment models (where no proposed date is offered to the patient), as each open invitation is generated, this will count as being due to take place 3 months minus 1 week (82 calendar days) from the date generated, until one of the following occurs:
  • the patient contacts programme centre to make appointment in which case the appointment is now counted as due on the new appointment date
  • the patient did not respond (DNR) by 82 calendar days in which case the appointment continues to be counted as due to take place 82 calendar days from the date generated

1.3       Denominator: number of individuals who had a due date for new, 12 or  24 month screening during the 12 month report period.

Caveats

Services without adequate capacity will have attendances that fall outside of the reporting period plus 6 weeks, therefore reducing the numerator figure for 1.1 and 1.2.

2.2 DES-PS02: Invitation for first routine digital screening (RDS) appointment

Description

This standard measures the proportion of people who had a new patient notification date were offered RDS within 89 days of that notification date.

Rationale

People can be diagnosed with diabetes several years after having developed the condition. It is therefore important that eye screening takes place as soon as possible after diagnosis to assess whether diabetic retinopathy is present.

Reference: National Institute for Health and Care Excellence (NICE) guidance for the management of diabetes type 1 and type 2.

Definition

Numerator: number of individuals newly added to the register who were offered a first RDS appointment date on or before 89 calendar days from that notification date

Denominator: number of people newly added to the register during the 3 month reporting period.           

Note, the 89 calendar day period includes 7 calendar days for any provider using an open appointment model to generate their invitation. The 89 calendar day period can be outside the reporting period.

Caveats

Any individual with a new patient notification date is included in the denominator. If individuals are excluded or suspended before an invitation for RDS is sent, they will not be counted in the numerator. Services can exception report these. For example,  if they are pregnant and move to digital surveillance, are medically unfit, or are under the care of HES for diabetic retinopathy.

Reporting does not distinguish between people newly diagnosed and those who are transferring into the service from another service.

2.3 DES-PS03: Routine digital screening (RDS) timely round length

Description

This standard is split into two separate metrics; 3.1 is timely round length for 12 month recall and 3.2 is timely round length for 24 month recall.

The terminology ‘round length’ means the time period between last screen and 1st opportunity to be screened again.

3.1 The proportion of people who were due a 12 month RDS appointment who were booked a new or 12 month RDS appointment that was due to occur no later than 6 weeks after their first or 12 month recall due date.

3.2 The proportion of people who were due a 24 month RDS appointment who were booked a 24 month RDS appointment that was due to occur no later than 6 weeks after their 24 month recall due date.

Rationale

People should be on the correct screening interval within RDS. To ensure that the correct screening interval is maintained, the invitation should be offered to enable the appointment to occur before or no later than 6 weeks after the due date. If the screening interval is not maintained, people may not be seen often enough, and detection of disease may be delayed.

Definition

3.1       Numerator: those in the denominator who had an initial booked appointment planned for before their due date or within the 6 weeks after their due date.

3.1       Denominator: number of individuals who had a due date for new or 12 month screening during the 12 month report period.

3.2      Numerator: those in the denominator who had an initial booked appointment planned for before their due date or within the 6 weeks after their due date.

3.2       Denominator: number of individuals who had a due date for 24 month screening during the 24 month report period.

Caveats

None.

2.4 DES-PS04: Slit lamp bio-microscopy (SLB) coverage and timely round length

Description

This standard is split into two separate metrics; 4.1 is SLB coverage and 4.2 is SLB timely round length.

The terminology ‘round length’ means the time period between last screen and 1st opportunity to be screened again.

4.1 The proportion of people with a due date for new or 12 month SLB who attended within the 12 month reporting period plus 6 weeks.

4.2 The proportion of people who were due a new or 12 month SLB appointment who were booked a new or 12 month SLB appointment that was due to occur no later than 6 weeks after their first or 12 month recall due date.

Rationale

Coverage for those on the SLB pathway

4.1 This standard gives an indication of the acceptability of the screening test in people eligible to have SLB. Services without adequate capacity will have attendances that fall outside of the reporting period plus 6 weeks, therefore reducing the count in the numerator.

Due dates are inferred from the last attendance dates, outcome and allocated recall timeframe.

New referrals to SLB will be given a due date 49 days after their date of referral. The denominator will then only include new referrals to SLB who were referred 7 weeks before the plus 6 weeks added to the end of the reporting period in the numerator. This is to account for the total 13 week timescale between screening and consultation detailed in PS13.

Timely round length for those on the SLB pathway

4.2 People who are moved to SLB surveillance need to be seen annually and may have complex needs due to other eye pathology. Therefore, the invitation should be offered before or no later than 6 weeks after the due date.

If the surveillance interval is not maintained, people may not be seen often enough, and detection of disease may be delayed. New referrals to SLB will be given a due date 49 days after their date of referral. The denominator will then only include new referrals to SLB who were referred 7 weeks before the plus 6 weeks added to the end of the reporting period in the numerator. This is to account for the total 13 week timescale between screening and consultation detailed in PS13.

Definition

4.1      Numerator: those in the denominator who attended a successful SLB event within the 12 month report period plus 6 weeks and were successfully screened.

4.1       Denominator: number of individuals who had a due date for new or 12 month SLB during the 12 month report period.

4.2      Numerator: those in the denominator who had an initial booked appointment planned for before their due date or within the 6 weeks after their due date.

4.2      Denominator: number of individuals who had a due date for new or 12 month SLB during the 12 month report period.

Caveats

None.

2.5 DES-PS05: Digital surveillance (DS) coverage and timely round length

Description

This standard is split into three separate metrics; 5.1 is DS coverage (people), 5.2 is DS coverage (appointments) and 5.3 is DS timely round length.

The terminology ‘round length’ means the time period between last screen and 1st opportunity to be screened again.

5.1 The proportion of distinct individuals with a due date for DS who attended within the 12 month reporting period plus 6 weeks.

5.2 The proportion of distinct instances of due date for DS which were attended within the 12 month reporting period plus 6 weeks.

5.3 The proportion of due appointments for digital surveillance that have an offer of an initial booked appointment due to occur within a reasonable time of the follow up period.

Rationale

Coverage for those on the DS pathway

5.1 This standard gives an indication of the acceptability of the screening test for people in the DS pathway.

5.2 This standard gives an indication of the acceptability of the frequency of the screening test for people in the DS pathway.

Due dates are inferred from the last attendance dates, outcome and allocated recall timeframe.

New referrals to DS will be given a due date 49 days after their date of referral. The denominator will then only include new referrals to DS who were referred 7 weeks before the + 6 weeks added to the end of the reporting period in the numerator. This is to account for the total 13 week timescale between screening and consultation detailed in PS12.2

Services without adequate capacity will have attendances that fall outside of the reporting period therefore reducing the count in the numerator. People moved into the DS pathway need to be seen on a regular basis. If the follow-up period is not maintained, people with diabetes may be seen too frequently or not often enough and detection of disease may be delayed.

Timely round length for those on the DS pathway

5.3 People who are moved to DS need to be seen on a regular basis and it is important that they attend their follow-up appointments in a timely manner.

Due dates are inferred from the last attendance dates, outcome and allocated recall timeframe.

New referrals to DS will be given a due date 49 days after their date of referral. The denominator will then only include new referrals to DS who were referred 7 weeks before the + 6 weeks added to the end of the reporting period in the numerator. This is to account for the total 13 week timescale between screening and consultation detailed in PS12.2

Definition

5.1       Numerator: those in the denominator who attended a successful DS event within the 12 month report period plus 6 weeks and were successfully screened (only 1 attendance will be counted per individual).

5.1       Denominator: distinct count of eligible people who had a due date for DS during the 12 month report period (only 1 due date will be counted per individual).

5.2       Numerator: count of distinct attendances for DS within the 12 month report period plus 6 weeks and were successfully screened.

5.2       Denominator: number of due dates categorised under DS at any point during the 12 month report period.

5.3      Numerator: those in the denominator who had an initial booked appointment planned within the expected interval (3, 6, 9 and 12months) of their due date period.

Recall period   Timeframe

3 months          +/- 1 week

6 months          +/- 3 weeks

9 months          +/- 4 weeks

12 months        +/- 6 weeks

5.3       Denominator: number of due appointments for DS in the 12 month report period.

Caveats

None.

2.6 DES-PS06: Pregnant women seen in digital surveillance (DS)

Description

The proportion of pregnant women with diabetes seen in DS within 6 weeks of notification of their pregnancy to the screening provider within.

Rationale

Pregnant women with diabetes have clear guidelines for the management of their diabetes as set out by National Institute of Clinical Excellence (NICE). Screening providers should comply with this guidance.

It is anticipated that any provider that sees women within 6 weeks of notification of their pregnancy, will be offered further appointment according to the NICE guidance.

The provider may be notified of the pregnancy by the GP, other health professional or they may be notified by the individual directly. In all instances the date of notification should be recorded.

Definition

Numerator: number of pregnant women attending a DS appointment within 6 weeks after notification to the screening provider who do not have an attendance date in the previous 89 days

Denominator: number of notifications of pregnant women received by the screening provider within the 12 month report period who do not have an attendance date in the previous 89 days

People excluded from this standard are:

• women diagnosed with gestational diabetes
• women already under the care of hospital eye services (HES) for diabetic retinopathy as they will remain under the care of HES for the duration of their pregnancy

Caveats

Women who are on the pregnancy pathway but who are no longer pregnant before attending their first DS appointment can be exception reported via local reporting processes.

2.7 DES-PS07: Routine digital screening (RDS) uptake

Description

The proportion of people attending a RDS appointment from those invited.

Rationale

This standard counts anyone due for RDS within the reporting period, irrespective of whether they are on a 12 month or 24 month pathway, who were sent an invitation for screening. This allows activity over the most recent year to be reported.

The numerator is different to coverage as it does not include the additional 6 weeks. This is because the denominator is reliant on a planned appointment being arranged. If this was attended in the 6 weeks after the report end date, this would inflate the numerator as the invite may not have been generated in the reporting period.

This standard gives an indication of the acceptance of the screening test in those offered the screen. Uptake should be looked at in conjunction with the DES-S01.

Definition

Numerator: number of people who have attended a successful RDS event within the 12 month reporting period, where images are captured such that a screening outcome can be determined.

Denominator: number of people offered a 12 or 24 month RDS event which was due to take place within the 12 month reporting period.

Caveats

The numerator can include instances where one or both eyes are not assessable through digital photography as an outcome.

People who are invited and then excluded before attendance remain in the denominator. People who are excluded before an invitation is issued will not be counted in the denominator.

Providers using an open appointment model may find that people invited but excluded prior to the reporting period are counted in the denominator.

Following the introduction of the 24 month pathway in October 2023, uptake is predicted to decrease from October 2024 for the following 12 months. This is because only those that attend can been selected for 24month RDS, leaving a higher proportion of non-attenders in the 12 month RDS pathway who will be due again from October 2024.

2.8 DES-PS08: Persistent non-attenders

Description

The proportion of people who have not attended any routine digital screening (RDS), digital surveillance (DS) or slit lamp bio-microscopy surveillance (SLBS) event in the previous 3 years.

Rationale

Counting people who do not attend regularly will allow providers to identify who this cohort is. Providers can then implement interventions to increase participation in this cohort.

The proportion of non-attendance should be looked at in conjunction with coverage standards DES-PS-01.1, 01.2, 04.1, 05.1.

Definition

Numerator: number of people on the last day of the reporting period in the RDS, DS or SLBS pathways who have not attended any event within the previous 3 years and have been on the register for at least 3 years.

Denominator: number of people on the last day of the reporting period in the RDS, DS or SLBS pathways who have been on the register for at least 3 years.

Caveats

The DS and SLBS pathways have been included in this standard from October 2024.

2.9 DES-PS09: Ungradable images in routine digital screening (RDS)

Description

The proportion of people where a digital image has been obtained but the final grading outcome is ungradable.

Rationale

The proportion of images with a final grading outcome of ungradable can indicate if there is a problem with the photography, grading process or equipment. It can also identify other eye pathology.

If a high or low ungradable rate is due to the process it may indicate there is a need for additional training within the service.

Definition

Numerator: number of people with a final grading outcome of ungradable in either eye following a RDS event which took place during the 3 month reporting period.

Denominator: number of people who have attended a successful RDS event within the 3 month reporting period, where images are captured such that a screening outcome can be determined.

Caveats

A small number of people will have eyes that are ungradable due to extensive media opacity, for example due to previous trauma. The clinical lead may decide to base the screening outcome and future screening method on the one gradable eye. This can lead to a higher rate of ungradable images.

It is recognised that local screening providers may recall people back to screening to have repeat photographs where adequate images were not captured at the initial screening appointment. For example, where people have refused dilating drops but have agreed to have these at a subsequent screening appointment. This can lead to a higher rate of ungradable images.

2.10 DES-PS10: Timeliness of issuing results letters

Description

The proportion of people attending for routine digital screening (RDS), digital surveillance (DS) or slit lamp bio-microscopy (SLB) to whom results were issued within 3 weeks of the screening event.

Rationale

To reduce anxiety for people who have attended an appointment, it is important that they receive their results in a timely manner. It is also important for the GP and relevant health professional(s) to be informed in a timely manner so that they can take appropriate steps in the ongoing care of people with diabetes.

Operationally, this standard also monitors if there is a backlog in the grading of digital images.

Definition

Numerator: number of result letters produced before or at 3 weeks of the screen date.

Denominator: number of people who have attended a successful screening event, within the 3 month report period. The screening event may be RDS, DS or SLB.

‘Produced’ may be printing a letter or creating an electronic result letter. This is a proxy measure for the receipt of result letters as it is not possible to measure if they are sent or received.

Caveats

People who are under the care of hospital eye services (HES) for other non-diabetic eye pathology may also be screened for diabetic retinopathy within HES and so will not receive a result letter from the screening provider. If an individual is moved to a deceased state within the software before the result letter is generated, those letters will automatically be cancelled, but the screening event will still be counted in the denominator.

2.11 DES-PS11: Timely referral of a screen positive outcome

Description

This standard is split into two separate metrics. 11.1 is the timely referral of urgent outcomes and 11.2 is the timely referrals of routine outcomes.

11.1 The proportion of people who are urgently referred (R3A) to hospital eye services (HES) within the 2 weeks following a screening event.

11.2 The proportion of people who are routinely referred (R2 or M1) to HES or surveillance within the 3 weeks following a screening event.

Rationale

It is important for people with diabetes with referable and potentially sight threatening disease to be graded and referred in a timely manner. This is the first step in the pathway for treatment and the provider should work to reduce unnecessary delays.

Definition

11.1     Numerator: the number of HES urgent referrals made before or at 2 weeks after the screen date.

11.1     Denominator: the number of people referred to HES with a final grading outcome of R3A in the worst eye, from a screening or surveillance event which occurred within the 3 month reporting period. The screening event may be RDS, DS or SLB.

11.2     Numerator: the number of routine referrals to HES or surveillance made before or at 3 weeks after the screen date.

11.2     Denominator: the number of people referred to HES or surveillance with a final grading outcome of R2 or M1 in the worst eye, from a screening or surveillance event which occurred within the 3 month reporting period. The screening event may be RDS, DS or SLB.

Caveats

If a person has been referred previously to HES, is screened again and a new referral is generated within the reporting period, both referrals will be counted.

2.12 DES-PS12: Timely consultation following referral for a screen positive outcome.

Description

This standard is split into two separate metrics. 12.1 is timely consultation of urgent outcomes and 12.2 is timely consultation of routine outcomes.

12.1 The proportion of people who are urgently referred (R3A) to hospital eye services (HES) and attend a consultation within HES within the 6 weeks following a screening event.

12.2 The proportion of people who are routinely referred (R2 and M1) to hospital eye services (HES) or to digital surveillance (DS) and attend a consultation within HES or DS within the 13 weeks following a screening event.

Rationale

An important part of any screening programme is for treatment to be available. It is important that an individual with R3A (urgent referral) diabetic retinopathy is seen in hospital and R2 or M1 (routine referral) diabetic retinopathy is seen in hospital or DS in a timely manner so that they can receive the appropriate management.

For R2 or M1 referrals, individuals should be seen in the same timescale regardless of whether they are referred to HES or DS, which may or may not include OCT imaging.

Although local screening providers are not directly responsible for providing ophthalmology appointments, they can work with HES to support this process so there is a seamless transfer of care.

Definition

12.1    Numerator: number of people referred to HES with a final grading outcome of R3A in the worst eye attending a first consultation before or at 6 weeks from their screening or surveillance event which occurred within the previous 3 month reporting period.

12.1:   Denominator: number of people referred to HES with a final grading outcome of R3A in the worst eye which occurred within the previous 3 month reporting period. The screening event generating the referral may be from RDS, DS or SLB.

12.2    Numerator: number of people referred to HES or a DS appointment with a final grading outcome of R2 or M1 attending a first consultation within 13 weeks of their screening or surveillance event, which occurred within the previous 3 month reporting period.

12.2    Denominator: number of people referred to HES or a DS appointment with a final grading outcome of R2 or M1 in the worst eye which occurred within the previous 3 month reporting period. The screening event generating the referral may be from RDS, DS or SLB.

Caveats

None.

2.13 DES-PS13: Timely consultation in slit lamp bio-microscopy (SLB) following an ungradable outcome.

Description

The proportion of people referred to slit lamp bio-microscopy (SLB) who attend an appointment for SLB within 13 weeks of their last digital screen.

Rationale

People whose images are ungradable at routine digital screening (RDS) or digital surveillance (DS) should be referred to SLB in a timely manner as they can still be screened and may have diabetic retinopathy.

People who are being seen in DS clinics with diabetic retinopathy (R2, M1, R3S) and become ungradable (for example due to cataracts), should be referred to HES and are therefore not included in this standard.

Definition

Numerator: number of people with ungradable image(s) referred to SLB during the previous 3 month reporting period who attended an appointment at a SLB clinic before or at 13 weeks from their last digital screen date.

Denominator: number of people with ungradable image(s)referred to SLB during the previous 3 month report period

Caveats

None.

3. Performance thresholds and other detail

4. Pathway themes 

NHS DES screening standards look at 5 themes to assess the pathway and 4 KPls are derived from standards DES-PS01.1and PS01.2, DES-PS08, DES-PS10 and DES-PS12. 

4.1 Theme: coverage 

• The related standards are:
• DES-PS01.1: 12 month routine digital screening coverage
• DES-PS01.2: 24 month routine digital screening coverage
• DES-PS04.1: Slit lamp bio-microscopy coverage
• DES-PS05.1: Digital surveillance coverage (acceptability of the digital surveillance test)
• DES-PS05.2: Digital surveillance coverage (acceptability of the frequency of the digital surveillance test)
• DES-PS06: Timely first attendance for pregnant women in digital surveillance

4.2 Theme: uptake 

• The related standards are:
• DES-PS01.3: Routine digital screening offered on 12 and 24 month recall
• DES-PS02: Newly diagnosed offered
• DES-PS03.1: Routine digital screening timely round length (12 month recall)
• DES-PS03.2: Routine digital screening timely round length (24 month recall)
• DES-PS04.2: Slit lamp bio-microscopy timely round length
• DES-PS05: Digital surveillance timely round length
• DES-PS07: Routine digital screening uptake for 12 and 24 month recall
• DES-PS08: Persistent non-attenders for screening and surveillance
• DES-PS13: Timely slit lamp bio-microscopy consultation

4.3 Theme: test 

• The related standards are:
• DES-PS09: Routine digital screening ungradable images
• DES-PS10: Timely result letters

4.4 Theme: referral 

• DES-PS11: Timely referral of people with diabetes with positive screening results

4.5 Theme: intervention

• DES-PS12: Timely consultation for people with diabetes who are screen positive

5. Resources to support providers and commissioners 

Additional DES operational guidance is included in the: 

• Screening guidance documents on gov.uk Diabetic eye screening: professional guidance - GOV.UK (www.gov.uk)
• service specifications are available on Futures NHS platform
• detailed programme performance report data lines and supporting dataset documents are available on Futures NHS platform

6. Reporting and publishing standards

Annual standards and quarterly KPI data are published on .gov. The data is collated by NHS England before publication

The data to support the DES standards is collected through submission of quarterly and rolling 12-month programme performance reports.

The 4 reports are submitted to NHS England, which calculate the standards. The standards are then validated by the provider manager and clinical lead. The screening providers obtain information on attended consultation dates from the hospital eye services they refer into. The hospital eye service is responsible for offering appointments to referred people with diabetes within the nationally specified time frames.

The programme performance report lines provide aggregate figures for important fields required to calculate the standards. These lines are specified in the following documents which are save on NHS Futures.

• Detailed description of pathway standard numerator and denominators
• DES performance report and dataset calculations
• Diabetic eye screening dataset

The standards are described in terms of the criteria used for the calculations in the database, but they have been written in plain English where possible. Where specific field options are given, these are the ones used in the above documents.